Need help about DEFINE_NET_REACTION_RATE
 

I get a global reaction mechanism from a detailed one, and want to simulation the reaction using Fluent. I use DEFINE_NET_REACTION_RATE, so the reaction rate of non-QSS species are easily defined, but I don't know how to pass the information of QSS spesies, such as molar or mass fraction. Usually, we can use C_UDMI(c, t,i) to pass some value, but how can I get the c and t in C_UDMI, it seems that the c and t in DEFINE_NET_REACTION_RATE is for particle. Could anyone help me? Or do you have other solutions? Need your help. Thank you very very much.